1. Field of the Invention
This invention relates to suspended vehicles adapted to run (move) suspended movable partition wall panels (hereinafter referred to as panels) as well as traveling and crossing rails for such a vehicle. More particularly, this invention relates to a suspended travel device which makes it possible to turn heavy panels with ease.
2. Description of the Related Art
Conventionally, suspended travel devices used for suspending and moving panels are of two types: one is a vertical wheel type which comprises horizontally elongated traveling rails each having a U-shaped cross-section open at the bottom. The sides of the rail are bent at the open ends inwardly and squarely, the end portions extending inwardly to form wheel bottom surfaces, leaving between them a space as a sliding groove. The traveling rail thus formed is installed near the ceiling of a room. A suspended vehicle with wheels rotatable in the vertical direction as those of a cart is installed inside the traveling rail, with its wheels being on the wheel base surfaces. A suspension axis which is to be connected with the upper end surface of a panel is suspended through the sliding groove from the vehicle body.
The other is a horizontal wheel type in which a suspension axis which is to be connected with a panel includes horizontal wheels directly mounted thereon.
Generally, what is required of such suspended travel devices are a stable traveling and an easy turning of the suspended vehicle. It is necessary for the vehicle to be turned when the relevant panel is to be moved for constituting the new partition or canceling the same.
The first type of suspended travel device, i.e., the vertical wheel type excels in the panel weight bearing capacity. However, its ability to make a turn, especially a square one, is rather poor. On the other hand, the second type with horizontal wheels offers a satisfactory ability to make a turn, especially a square one, but it is not suited to bear heavy panels. Examples of the former are disclosed in Japanese Patent Publications Nos. 50-20496, 60-7114, 60-7116, etc., and examples of the latter are disclosed in Japanese Utility Model Publication No. 55-24288, etc.
The problem with these prior art devices first lies in the fact that the suspension axis is hard to be held vertically in the sliding groove during the straight movement along the traveling rail. In the first type, the vertical wheels are liable to rub or hit against the inner walls of the traveling rail. In the second type, each of the horizontal wheels support the panel weight at a point on the lower surface thereof, so that it is apt to snake over the wheel bottom surface. In view of this, it has been attempted in the above described prior art to assure a balanced travel state for the suspended vehicle by a complicated configuration of the wheel sheath or by provision of induction wheels, but no satisfactory result has been obtained yet, which is especially the case with devices for heavier panels. This is mainly due to the excessively great rising height of the suspended vehicle and its large dimension in the transverse direction.
As for the panel turning in the traveling rail, it is conventionally effected, in the case of a vertical wheel type suspended travel device, by providing at each crossing (branching) section a line gently curved with respect to the straight rail section. In a horizontal wheel type suspended travel device, turning is effected by a square crossing of the rails. Recently, more and more vertical wheel type devices have come to employ the square crossing method in view of the convenience in arranging panels as well as from the aesthetic point of view. In an example of such a construction, a vertical wheel is mounted on each of the four side surfaces of a parallelepiped vehicle body (as disclosed, for example, in Japanese Patent Publication No. 62-17062).
The present invention is directed to this kind of suspended travel vehicle, i.e. the one in which the vertical wheels and the square crossing method are combined.
Whether in the curve turning method with a curved line or in the square turning method, rails of the same configuration are to be integrally formed in a continuous configuration, with the bottom opening thereof being directed downwardly, so that, at a crossing rail section, the wheel base surfaces are in an interrupted condition, the wheel sheath being enlarged and a large inner space left in the section. As a result, the wheels, not supported by the wheel bottom surfaces, are inclined, so that the suspended vehicle becomes unstable in the wheel sheath thus enlarged, so that its body or wheels are apt to come off the path to get in the sliding groove or hit against the inner walls of the wheel sheath.
To cope with this, a contrivance has been proposed in the prior art device regarding the square turning of the vertical wheels (Japanese Patent Publication No. 62-17062). According to this contrivance, the vertical wheels are not used in the crossing sections, i.e. they are kept in the air while the vehicle is traveling along crossing rail sections. Instead, large balls (made of steel) are provided in four corners of the upper portion or lower portion of the vehicle body for sustaining the suspended vehicle at the crossing sections. The problem with this prior art device is that when balls are provided at the lower position of the vehicle, they are hard maintain at the same height as the wheel bottom surfaces and that when they are provided at an upper position of the vehicle, a satisfactory engagement is hardly attained between the balls and the suspension columns in the crossing section. Further, the ball and the traveling rail are only in a point contact with each other, so that a smooth rotation cannot be effected. As far as the direct movement along the traveling rail is concerned, the body of the vehicle of this prior art device effectively prevents the suspended vehicle from swaying because of its configuration fully occupying the wheel sheath of the traveling rail and provides a satisfactory running condition by small horizontal wheels adapted to rotate as they operatively engaged with the rail walls. In the crossing rail sections, on the other hand, the enlargement as mentioned above of the wheel sheath makes the horizontal guide wheels useless, so that unless the panel is accurately pushed ahead, the suspended vehicle cannot be made to move in the intended direction, because the rotations of the balls are not regulated.
Moreover, such balls cannot offer a sufficient capacity for bearing heavy panels. For heavier panels with a weight over 100 kg, especially for those with a weight over 500 kg, the above described contrivance is not suited. Generally speaking, the traveling problems in the crossing sections of a suspended travel device have not been overcome yet.